Continuous screw press



w. MGD'ONALD I, l1,785,041

CONTINUOUS SCREW VPRE-ss Filed oct.

5 Shets-Sheet 2 @mum De. v16, 1930.

Dec. 16, 1930.

W. MCDONALD,v

CONTINUOUS scREw PRESS A Sheets-Sheet 3 Filed Oct, 1,-1926 w. McDoNALD Y coNTINUUs SCREW PRESS Filed oct. 1`, 1926 mssm Dec. 16, 1930 w. MDoNALb CONTINUOUS SCREW PREsS lFiled ot. 1; 192e 5 sheets-sheet 5 y' lthe solid portions is greater than Patented 16, 1930 "UNITED, :STATES llixrlaNT ori-fics 'WILLIAM McboNALI1,oI CHICAGO, ILLINOIS, AssIeNoR cro` swrr'rfl a Gournay, or

1 emesso, ILLINOIS, A coRPoRATIoNoFILLI-NOIS eoNTINUoUs applicati@ mea 'october 1, 192s.- Asemi No. 138,885.

My invention relates to improvements in 'a type of screw presses used in various arts vfort-he purpose of expressing the liquid constituents of the material acted upon,` and the particular embodiment of my invention,

hereinafter particularly described is dey signed and adapted to separate oil and grease from cooked cracklings consisting. of meat y trimmings, honey andgristly port-ions of, 1o meat,'condemned carcasses and miscellaneous similar packing houseofal. f

' In the packing industry, it is usual, in utilizing suchportions`of meat'4 carcasses, to cookthevmaterial in steam jackete'd vessels,

l wherebythe moisture is drivenlof'from the solids and the4 grease cells broken down. y.

. In the casejof materials having a high grease Vcontent,` the free grease may be drawn off I during the'cooking operation, or drained off 2G lfrolnfthe cooked cracklings, at its conclu-sion. .-'I-'here remains a considerable quantity of grease, however, adherent `to and contained` in the solid cracklings, which cannotbethus removed, and in some cases hydraulic presses,

and'in others continuous screw pressesof the type to which my invention relates, have been used, but the amount of grease remaining vin for best utilization of the solids.

contain a largeproportionof protein, besides the residue of grease, and, when dried and ground form. la nutritious and valuable .stock food. Too large a proportion of fat in the product, however, isdetrimental to the asa-les loss in produce. s

-It' is therefore, important to express as much of the grease' as possible from the Ic'oQked material, and-the object of my inven-..

obtain an increased yield of fat, and also a more desirable residue of the solid materials.

. struction ofthe feed chamber at this point where the material enters the vcompressionchamber of the machine, whereby bridging of materia-l'passing through the feed chamber. is avoided and the formation 0fvoies in desirable The Solidsy development offpoultry., as wellas producing f To this end'I have devised an improved conthe stream of material is avoided, and where-v by', also, the material is partly compressed before entering the compression chamber;

and I havealso. devised an improved construction of the worm lextending through the feed l. and compression chambers, which .acts to break down bones and'solid pieces of ma- -terial, and further serves to' prevent bridging-of the material andv the formation of voids, the form of thefeed chamber and action of the screw thus Icausing an yeven feed ,and iiow of material and uniform and in; creased pressure in thel compression chamber which vresultsin increased Aefficiency in action of the machine. f l 'j In the drawings', Figurel isatop; plan Aview of my improved continuous'screw press; Fig. 2 is a side -view'o'f the same; Fig. 3' is a horizontal section of-the centralh'po'rtion of lthe machine taken 'in a plane extending ax! ially ofthe'compression chamber and ona larger scale than Figs; l and 2; Fig. 4, is a vertical cross-section in a' plane indicated the dotted linee-4 of Fig. l and on the same scale as FlgQ; Fig. 5 isacentral vertical section of'the portion of the machine adjacent the feed end of the feed screw and feo also on'the samescaleas Fig. .3; Fig. 6 is a verticalc'ross-section through the compres` detail of the same parts, partly in section,

as indicated by Fig. 7. u 'Like reference characters indicate like parts on' all the figures of the drawings;

intthe drawings and in which my invention is embodied, the f1 ame work which'may be vari'ouslylconstructed, preferablyv consists of.

metal membersl X-rigidly bolted or otherwise *secured together and arranged to suitably support the moving andstationary elements of the machine. The crackling hoppe'rvl, in the bottomof--which is, arranged a wormA 2, is arranged to deliver the -cracklings through a chute 3 to one end of a steam-j acketed drum 4 in which is arranged a helical conveyor 5 the. dotted lines' 8 8 of vDescribing briefly the machine illustrated v arranged to convey the material to a feed chute 6 which at its lower end communicates with the feed chamber 7 adjacent the feed end of the feed screw 8. An inclined spiral feeding Worm 9 extends downwardly in said feed chute to the upper front or entrance side of the feed chamber. The wall of this feed chamber (see Figs. 3, 4 and 5) is contiguous to the feed screw 8 along its bottom, and spreads laterally from rear to front below the bottom of and in the path of the material delivered by said spiral feeding worm 9, which is ankimportant featureof my invention, as will be hereinafter explained. The rear side of the feed chamberfopens into the pressure barrel or compression chamber of the machine, which inthe present instance is of built-up construction andfor the purpose of complete 'exposition may here briefly be described. The barrel frame includes a pair of upper bars l0, bolted to frame members 11, between which are clampedpby means of bearing clamping bolts 12, a series of spaced retaining blocks 13 arranged between the bolts. The blocks 13, which are arranged in pairs have semi-cylindrical inner faces and are secured together in spaced relation by means of -spacing bars 14 let into the upper bars and 14a let into the meeting faces of the lower bars. The bars 14 and 14a. extend radially inward beyond the curved faces of the blocks 13 and themselves have curved inner faces which form part of the pressure barrel. Between the side faces'of the bars 14-14a and an upper clamping bar 15 and a lower clamping bar 16 are arranged a series of slats 17 extending edgewise from the curved faces of the blocks 13 radially of the barrel structure, these slats together constituting the larger part of the pressure barrel. The. upper and lower clamping bars 15 and 16, before mentioned, have wedge-shaped side faces adapted to cooperate with the adjacent slats 17 in such manner that when the bars are drawn outwardly by clamping bolts 18 having a bearing on longitudinal bars 19 bearing on the upper and lower blocks 13, the slats will be squeezed in four groups be- .tween the bars 14 and 14a, and the bars 15 and 16.

As illustrated in Figs. 7 and 8, the side faces of the slats 17 are cut back to leave a side flange 17a, and this flange is formed with minute semi-conical notches 20 which constitute the orifices for escape of grease from the material pressed within the barrel. The slats are held in radial alignment by spacing rings 2l let into selected blocks'13 at intervals, and notched on their inner faces to engage the outer Aedges of the slats.

lVithin the pressure barrel are arranged in axial alignment the principal screw members of the press, consisting o the feed'screw 8 before mentioned and the pressure screw 22, the former being arranged to rotate at a higher speed than the latter and a suitable ratio being 3% to 1. The pressure screw is keyed to a long main shaft 24 journaled in the frame Work of the machine, and the feed screw 8 is mounted on' a sleeve 21, rotatably mounted on said main shaft. As usual, the central body of the 'pressure screw 22 is tapered so that the lspiral passage between the thread is constricted towards the rear, and at the rear end of the press the annular outlet orifices for the pressed material is yieldingly obstructed by an 'annular springpressed retarding block 23 having feathered connection with the main shaft 24 to which the pressure screw 22 is fixed, so that it ro tates with the latter. A- thrust block 25, threaded on said shaft` 24 and which may be rotated'by a hand lever 26 pivoted on the block and having a ratchet connection therewith, provides means for varying the stress of the spring 27 which tensions the block 23.

As illustrated in Figs. 3, 4 and 5, the front end of the feed screw 8, adjacent the front and wider side of the feed chamber and opposite' the lower end of the feeding worm 9 isformed with two diametrically arranged notches which provide a pair of teeth on the screw thread at that point, this construction constituting another important feature of myinvention. Two notches are shown but the number is not restricted.

The operating connections for the machine may suitably include, as illustrated, a pinion A on the shaft of the 'electric motor used for power, meshing with a pinion B secured to a shaft to which is also secured a pinion C which meshes with a gear wheel D on a shaft D. To the shaft D is also secured a sprocket wheel E engaging a sprocket chain which drives a large sprocket wheel F. The latter wheel is securedto a shaft to which is also secured a pinion G engaging a large gear wheel H which is secured to the main shaft 24 before mentioned and thus rotates the pressure screw 22.

The shaft D before mentioned also carries a pinion I meshing with a large gear wheel .l secured to the sleeve 21 to which the feed screw 8 is secured.

The helical conveyor is mounted on a long shaft 5a which is driven through a spocket wheel K on the main shaft'24 of the machine, a sprocket chain and a sprocket wheel L on said shaft 5a. The shaft 5" also carries a gear wheel M meshing with a pinion N on al shortshaft to which is secured a bevel pinion O meshing with a bevel pinion `P on the shaft to which the spiral feeding worm 9 is secured.

The worm 2 in the crackling hopper is in the present instance driven intermittently b v means of a gear wheel Q on the shaft 5 hcfore mentioned, `a small pinion R meshing therewith, a crank arm S on the shaft of said pinion, a connecting rod T pivoted to an oscillating arm U, and a ratchet on said arm arranged to cooperate with a ratchet wheel worm-is secured.

In' the operationof the machine, the mass of cracklings passing vthrough the chute 6 is delivered into the front or larger end of the which is secured to the shaft to .which said feed chamber? through the action 'of the prelim'inary feeding screw 9, which is rotated at such speed as to create a slight pressure'in thefeed chamber. This feeding'worm, it will be noted, is of vgradually increasing diameter from topto bottom'and arranged at one side ofthe passageway for material through 4the chute, a 'construction and arrangement which large'bones or masses o'r chunks of gristle or other tough material. delivered to thenotched portion of the feed screw by the'feeding Worm are carried not only rearwardly into the` constantly narrowing spaces at the downwardly moving side of the screw, but also' down# wardly as well toward the line of contactbe-r 4 vtween the bottom, ofthe feed screw and the ber and incomplete separation of greasefrom feed chamber', with .the result that such masses are brokenup and fed onward between thel turns of the thread of the feed screw, ,instead of riding on the outer faceof the thread, as

frequentlyoccursin other machines of this ty'pein which' the worm is not-notched. The

result of the formation of voids in suchv other machines is a material reduction ofthe normal pressure within the compression cham-' the material being acted upon.- -The inclined walls of the feed chamberjin `my improved y machine, in connection with the free,unob

structed iiow ofinateral into-such'feed chamber, causes a higher and more constant pressure to be maintained in the compression chamber' than in'machines not having the form off-feed chamber and feed worm described,` and. consequently results in a more nearly completeseparation of the grease from the solids. n

I claim 1. A continuous screw press ofthe charac?" ter described and having, acylindrical compressionachamber and' a screw member arf ranged to force Vthe material operated upon therethrough, said press being formed'withv .a feed chamber in axial alignment with the compres-sion chamber and with a transverse feed. chute opening into said feed chamber,

chamber and being formed opposite the feed chute opening with notches havinga crushing action arranged to engage and *break up large fragments 0f material entering said chamber through said jopening, andthe wall of'saidv feed-chamber spreading from the front end of the 'comone side of spaced peripheral pression 'chamberlaterally and forwardly away from theiscrewmember.

2. A' continuous screwpress 4of the character described and having a cylindrical comf pression chamber and al screw member-arf ranged to force'the material "operatedupon therethrough, said press being formed'with a feed chamber in axial alignment with the compressionchamber and with afeed chute opening transversely into said feed chamber and said screw member ,extending i-nto said feed chamber, and said press having an open center feeding worm arranged at one side of the passageway through the feed chute. 3. A continuousscrew press of thefcharacter described and havingV a cylindrical compression chamber and ascrew member` ar ranged to force the' material operated upon y therethrough, said press being' formed with a feed chamber in axial alignment with the 'compression chamber and with a'feed chute opening transverselyv into said feed'chamb'er andsaid screw member extending/into' said feed chamber, and said press having an inclined feeding worm of gradually increasing diameter from .top 'to 'bottom arranged vat the passageway through the feed chuteffn "4. A continuousv screw press of the. character described and having' a cylindrical compression chamber and ascrew member arran'gedto force the material operated upon therethrough, said 'press beingformed with 'a feed chamber in axial alignment' with the compression chamber andwith a feed-chute opening transversely into said feedchamber and said screwmember extendinginto said feed chamber, and theA walls of said feed Achamber spreading from thefront end of the compression chamber forwardly away from the screw member, and said screw press also having an inclined feeding worm arranged' atone side of the passageway through the'feed chute. 1

5. A screw press accordingv to vclaim 4 in which said feeding worm isan open-center spirally-coiled member off gradually increasing diameter from top to bottom'.

6; A :continuous screwpress of `the char! acter vdescribed and having .a1-'cylindrical compresslon chamber and a. screw `lmember arranged to force thematerial operated upon therethrough, said press being formed'witha feed chamber in axial alignment with' the 4conipressi'on c hamberand with a'vertical feed chute opening at its bottoml into said'feed `chamber said screw member eXtendin into said screw member extendlng into'said feed g ripheral 'notches having a crushing action ar-l rangedl to e-ngage` and break up largefragments of material entering said chamber throughsaid opening, and-the 'wall of said 'i feed chamber spreading laterally away fromv said. screw member from rear to front opposite said feed chute opening and being contiguous along its bottom to said screw member.

7. A continuous screw press of the character described and having a cylindrical compression chamber and a screw member arranged to force the material operated upon therethrough and having also a feed chamber in axial Aalignment with the compression chamber and a feed chute opening transversely` into said feed chamber and a spiral feeding member in said feed chute, said screw'member extending into said feed chamber and being formed opposite said feeding member I5 with spaced peripheral notches having a crushing action arranged to break up large fragments of material delivered by said feed member to the notched portion of said screw member.

20 8. A continuous screw press of the character described andv having a cylindrical compression chamber and a screw member arranged to force the material operated upon therethrough and having also a feed chamber 25' in axial alignment with the compression chamber and afeed chute opening tramversely into said feed chamber and a spiral feeding member in said feed chute, said screw mem-- ber extending into said feed chamber and 33 being formed opposite said feeding member with spaced peripheral notches having a crushing action arranged to break up large fragments of material delivered by said feed member to the notched portion of said screw 35 member, and the walls of said feed chamber spreading from the front end of the compression chamber forwardly away from the screw member. 9. A continuous screw press ofthe char- 40 acter described and having a cylindrical compression chamber and a screw member arranged to force the material operated upon therethrou h and having also a feed chamber in axial a ignment with the compression chamber and a vertical feed chute opening .at its bottom into said feed chamber and a spiral feeding member in said feed chute, said screw member extending into said feed chamber and being formed opposite said feeding memro ber with spaced peripheral notches having a crushing action arranged to break up large fragments of material delivered by said feeding member to the notched portion of said screw member. and the wall of said feed is chamber spreading laterally away from said screw member from rear to front in the path of said feeding member and being contiguous along its bottom to said screw member. In .testimony whereof, I have subscribed C0 my name.

wiLLIAM MCDONALD. 

